pcm: Partial Credit Model Derived Probabilities
In classify: Classification Accuracy and Consistency under IRT models.

Description Usage Arguments Details Value Examples

Calculate vector of probabilities of success from person and item parameters under the Partial Credit Model.

1	pcm(theta=NULL, delta=NULL, n=NULL)

`theta`	Theta parameter
`delta`	Vector of delta parameters
`n`	Number of item categories

The delta parameters are the intersection points of adjacent category information functions. There should be one less delta parameter than categories.

Vector of probabilities of success

# Example from The Theory and Practice of Item Response Theory
# By Rafael Jaime De Ayala
# p.204
theta <- 0
n <- 3
d <- c(-1,1)

pcm(theta,d,n)

#0.2119416 0.5761169 0.2119416